Despite the hard, bitter winter, the animals work to rebuild the windmill, which the humans claim fell because of its thin walls. Though the pigs say the humans' claim is a lie, they make the new windmill's walls three feet thick.
The animals trust the pigs' lies rather than the obvious truth because they still believe blindly that "Four legs good, two legs bad!"
In January, the farm's food supply runs out. Even though it seems possible the animals could starve, the pigs hide the food trouble from the humans, escorting Mr. Whymper through a storehouse made to appear full of food.
Under Stalin's catastrophic Five Year Plan, the USSR suffered famines that killed millions. Stalin covered up the tragedy.
Napoleon now issues almost all orders through Squealer, who one day announces that the hens must give up four hundred eggs a week to pay for grain and feed. The hens angrily refuse. Napoleon responds by cutting the hens' rations. He also declares that any animal that feeds the hens will be killed. After five days, during which nine hens starve to death, the hens give in.
By tricking the animals into thinking Animalism and Animal Farm are the same, the pigs can kill or punish anyone who disagrees with their orders and claim they're defending Animalism. It's slavery disguised as freedom.
At about the same time, Napoleon enters negotiations to sell some wood to either Pilkington or Frederick. Whenever he's close to a deal with Pilkington, rumors circulate that Snowball is hiding at Frederick's farm, and vice versa.
Before WW II, the USSR negotiated possible treaties with both the Allies and the Germans, playing the two sides against each other.
In addition, Squealer soon announces that Snowball has been sneaking onto Animal Farm at night: Napoleon can smell him. Squealer tells the animals that Snowball was Jones's "secret agent" from the beginning. He reminds them how Snowball tried to betray them at the Battle of the Cowshed and Napoleon saved the day.
The pigs aim to rewrite Animalism and all of Animal Farm history. If they can get the animals to fear Snowball, they can use Snowball to justify their own rule, as they once used Jones.
Boxer disagrees. He says he thinks Snowball was loyal at the beginning, even if he later turned traitor. When Squealer responds that Napoleon himself has stated that Snowball was a traitor from the beginning, Boxer changes his mind and says then it must be true. Still, Squealer gives Boxer a dark look and warns the animals to be on the lookout for Snowball's secret agents.
Boxer believes so much in Animalism that he believes Napoleon's statement about what happened even over his own memories. But just the fact that he voices his memories at all makes Squealer see him as a threat.
Four days later, Napoleon calls for an assembly in the yard. When the animals gather, Napoleon whimpers and his dogs attack Boxer and the four pigs that had questioned Snowball's removal. The pigs are bloodied, but Boxer repels the attack and pins one of the dogs to the ground. Boxer glances at the stunned Napoleon to ask what he should do. Napoleon orders him to let the dog go and then commands the pigs to confess. They confess, and the dogs kill them as traitors to Animal Farm. A series of other animals also confess: all are killed.
Stalin "purged" the Soviet government by torturing those he considered enemies until they admitted to crimes they hadn't committed. Then he had them killed. Napoleon considers Boxer an enemy because Boxer remembers the past correctly. And Boxer can't comprehend that Napoleon just attacked him.
In the aftermath of the assembly, the animals are miserable, having witnessed the first killings on the farm since Mr. Jones was defeated. Boxer thinks he must work harder to make things better. Clover leads the animals in a sad rendition of "Beasts of England." Squealer soon announces that "Beasts of England" has been forbidden: it was a song of revolution, and the revolution has ended. A pig named Minimus has composed a new song: "Animal Farm, Animal Farm, Never through me shalt thou come to harm."
After the purge, Napoleon and his pigs officially kill the revolution by banning the song "Beasts of England." As the new masters of the farm, the pigs fear the ideas in that utopian and idealistic song, and replace it with a propaganda song that defines the state as more important than the individual.